“protein bound”

We have one entry that includes the term protein bound.

protein-bound iodine

noun

: the amount of iodine expressed in micrograms per 100 milliliters of blood serum that is precipitated with serum proteins and that serves as a measure of the activity of the thyroid gland

See the full definition

Word of the Day

Listen to the pronunciation of tribulation

See Definitions and Examples »

Test Your Vocabulary

Name That Flower

  • any of a genus helianthus especially h annuus of new world composite plants with large yellow rayed flower heads bearing edible seeds that yield an edible oil
Spell It

Hear a word and type it out. How many can you get right?

TAKE THE QUIZ
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.

Pick the best words!

PLAY
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Word Game Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
Missing Letter A daily crossword with a twist
spelunker-silhouette
People of Interest Quiz Can you tell the "sommeliers" from the "spelunkers"?